Various types of construction of revolving card flats are known from the prior art. Revolving card flats are used in carding. The revolving card flats employed currently consist essentially of a card-flat bar with a clothing. The card-flat bar is composed of a card-flat foot and web lying above the latter. The clothing is fastened to the card-flat foot with the aid of clips. The clothing itself is used in the form of clothing strips, on the underside of which a multiplicity of clothing needles in the form of small wire hooks are fastened. At the two ends of a card-flat bar, devices are provided which makes it possible to fasten the card-flat bar to a chain or a belt.
U.S. Pat. No. 581,749 discloses a revolving card flat and a corresponding tool for fastening the clothing strip to the card-flat foot. In this case, first, the clips are connected to the clothing strip. In a further step, the clothing strip is joined together with the card-flat bar, and subsequently the free portions of the clips are bent around the card-flat foot, so that the clothing strip comes to lie, free of play, on the card-flat foot. The card-flat foot is in this case surrounded by the clips in a bracket-like manner. To make the connection between the card-flat foot and clothing strip by means of clips, a complicated movement of the two used is necessary.
DE 128 552, likewise, discloses the fastening of a flexible clothing in the form of a clothing strip to the card-flat foot of a card-flat bar. The clip used in this case, on the one hand, engages into the foundation of the clothing strip and, on the other hand, engages around or surrounds the card-flat foot. This makes it possible for the lining material of the foundation of the clothing strip to lie firmly on the card-flat foot. Here, too, the disadvantage is that clips bent on both sides have to be manufactured.
FIG. 1 shows a device, such as is used for drawing clothing strips onto card-flat bars. The card-flat bar 1 is built onto a clothing strip 10 previously laid into a holding device 8, so that the card-flat foot 3 comes to lie on the clothing strip. The clips 5 are already fastened to the clothing strip 10 on longitudinal sides of the latter. The card-flat bar 1 is consequently introduced with the card-flat foot 3 between the clips 5. With the aid of prebending rollers 6, the clips 5 are performed. In a second step, by means of the form rollers 7, the clips 5 are integrally formed onto the card-flat foot 3. The prebending rollers 6 and form rollers 7 are moved in the longitudinal direction of the card-flat bar 1 for the integral formation of the clips 5, while the rollers rotate and are pressed against the card-flat foot 3. The device shown has the disadvantage that only a specific shape of the card-flat foot 3 fits together with the predetermined form rollers 7. Also, complicated movement and clamping mechanisms are necessary so that the operation described above can be carried out.
WO 2006/039829 discloses a further example of a device for attaching a clothing strip to a card-flat bar. A prepared clothing strip, in which the clips are already fastened with a first portion on both sides, is introduced into the device. The card-flat bar is subsequently introduced into the device with the card-flat foot against the clothing strip so that the clips lead with a second portion along the longitudinal sides of the card-flat foot. The bending cheeks of the device are then pivoted inwards against the card-flat bar, with the result that the third portion of the clips is integrally formed onto the card-flat foot. To generate the necessary holding force, in addition, a deformation of the clips along the longitudinal sides of the card-flat foot is generated by means of press battens. One disadvantage of the device is that a plurality of movements of pressing tools and bending cheeks are necessary in order to achieve a fastening of the clothing to the card-flat bar. Also, there is the risk that, in the case of excessive deformation of the clip, a change in shape of the overall card-flat bar may occur, because various elements of the card-flat foot are spanned by the clips.
The prior art for fastening clothing strips to card-flat bars with the aid of clips likewise entails the disadvantage that the card-flat foot has to be subjected over its entire length and width and also its height to a narrow manufacturing and dimensional tolerances. In order to achieve a reliable fastening of the clothing strips, an exact coordination of the pressing tool, form rollers, dimensions, and shape of the card-flat foot with the dimensions of the clips and their material properties is necessary. This leads to a cost-intensive production of the individual parts and also of the equipment necessary for assembling them.
An object of the present invention, then, is to avoid the disadvantages of the prior art and to provide a simple connection between the card-flat foot and clothing, without having to allow for any loss of holding force.